What Causes Swelling And Boils On Foreskin?

Every time I have sex about a day later my skin on my shaft swells and is painful to the touch, I also notice little pimple maybe blisters along the swelling, if I squeeze hard enough I can get a clear liquid out of it. I have been diognosed with herpes and have had outbreaks where I get a real blister, this looks nothing like it or act like it when i have had herpes outbreaks... Also where the pimple looking heads are leaves a scar if they burst which herpes does not...... It looks like lympthcole to me, or I had a vasectomy 8 weeks before my first episode of this...... Any ideas????